[Isolated vertigo in vertebrobasilar ischemia--does it exist?].

An isolated vertigo may occur in vertebrobasilar ischemia, especially as the first symptom of cerebellar ischemia or basilar artery occlusive disease. Based on neuroanatomical findings, these short-lasting vertigo attacks result from transient insufficiency of the anterior inferior cerebellar artery (AICA), which supplies the inner ear and leads to ischemia of the upper parts of the vestibular labyrinth. Persisting vertigo with or without lateropulsion may occur in cerebellar infarctions with involvement of the medial inferior hemispheres due to occlusion of the medial branch of the posterior inferior cerebellar artery. Caloric testing with oculography can usually differentiate cerebellar infarction and peripheral vestibular disease. Since ischemic lesions with AICA insufficiency may cause pathological results in caloric testing, both clinical and neurophysiological analysis of associated oculomotor signs is essential for a correct diagnosis.